ref: d110794e66d44f71191c74a10a079a1951a893a6
dir: /repeat/repeat.c/
#include <u.h> #include <libc.h> static void usage(void) { print("usage: %s -l len_frames [-t times] [-c channels] [-f file]\n", argv0); exits("usage"); } void main(int argc, char **argv) { int length, chan, t, f, r, n; u8int *b; length = 0; chan = 1; t = -1; f = 0; ARGBEGIN{ case 'l': length = atoi(EARGF(usage())); break; case 't': t = atoi(EARGF(usage())); break; case 'c': chan = atoi(EARGF(usage())); break; case 'f': if ((f = open(EARGF(usage()), OREAD)) < 0) sysfatal("%r"); break; default: usage(); }ARGEND if (length < 1) sysfatal("invalid length: %d frames", length); if (chan < 1) sysfatal("invalid number of channels: %d", chan); length *= chan * 4; if ((b = malloc(length)) == nil) sysfatal("couldn't allocate %d bytes", length); n = 0; while (t != 0) { if (f != 0 || n == 0) { seek(f, 0, 0); for (n = 0; n < length; n += r) { r = read(f, b+n, length-n); if (r < 0) exits("read failed"); else if (r == 0) break; } memset(b+n, 0, length-n); } if (write(1, b, length) != length) break; if (t > 0) t--; } exits(nil); }